Do not update toolbar when selection was lost

[ArneBab]

This fixes an issue in Chromium and Chrome: When the toolbar size selection is opened, the selection of the text is lost and the size selection does not show the currently selected size.

In Icecat (Firefox 78) the text selection is not lost upon opening the size selection, therefore the issue does not appear.

The change here causes the menu to keep the highlighting of the size of the currently selected text.

It does not cause the selection to persist.

[ArneBab]

The issue this fixes can be reproduced in the interactive playground: https://quilljs.com/playground/

It happens in Chromium

Select some text

Open the size selection menu entry: It does not show the current size and the text in the text field is no longer selected

The list of sizes shows the highlight of the current size for a moment, then it flickers and the highlighting of the current size is gone along with the selection of the text.

But not in Icecat (Firefox)

Open the size selection menu entry: the current size is highlighted in blue and the selection in the text field persists